Abstract: The phase relationship between two clock signals in an integrated circuit (IC) is determined by transforming each of the clock signals into a data word, where bit transitions in the data word represent signal transitions in the clock signal, and comparing the two data words. For example, in an IC having a de-serializer as part of its input/output logic, the clocks are sequentially multiplexed into the de-serializer, which transforms the clocks into parallel-format data words. The resulting words corresponding to the first and second clock signals can then be compared to determine clock signal transition differences and thus the phase relationship between the corresponding clocks signals.

Abstract: A Serializer/De-serializer (SerDes) of an integrated circuit (IC) includes selectable inputs and outputs not only for functional data and boundary scan (e.g., JTAG) test data, but also for parallel-scan test data. The serializing portion of the SerDes includes multiplexing logic responsive to control signals to select or identify one of the multiplexing logic inputs for functional data, boundary scan data and parallel-scan data. The de-serializing portion similarly includes selection logic responsive to such control signals to select or identify one of the selection logic outputs for functional data, boundary scan data and parallel-scan data. The multiplexing logic and selection logic couple the selected input or output, respectively, to the SerDes input/output pads.

Abstract: The phase relationship between two clock signals in an integrated circuit (IC) is determined by transforming each of the clock signals into a data word, where bit transitions in the data word represent signal transitions in the clock signal, and comparing the two data words. For example, in an IC having a de-serializer as part of its input/output logic, the clocks are sequentially multiplexed into the de-serializer, which transforms the clocks into parallel-format data words. The resulting words corresponding to the first and second clock signals can then be compared to determine clock signal transition differences and thus the phase relationship between the corresponding clocks signals.

Abstract: A Serializer/De-serializer (SerDes) of an integrated circuit (IC) includes selectable inputs and outputs not only for functional data and boundary scan (e.g., JTAG) test data, but also for parallel-scan test data. The serializing portion of the SerDes includes multiplexing logic responsive to control signals to select or identify one of the multiplexing logic inputs for functional data, boundary scan data and parallel-scan data. The de-serializing portion similarly includes selection logic responsive to such control signals to select or identify one of the selection logic outputs for functional data, boundary scan data and parallel-scan data. The multiplexing logic and selection logic couple the selected input or output, respectively, to the SerDes input/output pads.

Abstract: A method and system for remotely testing an integrated circuit installed in an integrated circuit system is presented. The integrated circuit is equipped with test structures for testing functional blocks within the integrated circuit, and a test access mechanism configured to receive test vectors for controlling the test structures. Test vectors are applied, via the parallel port of a remote computer and parallel cable, to pins of the parallel port of the integrated circuit system, which are connected to the signal ports of the test access mechanism implemented in the integrated circuit of interest, thereby allowing remote testing of the integrated circuit while the integrated circuit is installed in its native system.

Abstract: A method and apparatus is presented for measuring jitter tolerance in a device under test. A device under test is established to operate at a specific frequency. A bit pattern is generated from a bit pattern generator. The bit pattern generated by the bit pattern generator is produced at a frequency that is a multiple of the frequency that the device under test is operating under. Bits are systematically changed in the bit pattern and then errors are measured in the device under test. As a results the jitter tolerance of the device under test is measured.

Abstract: A method and apparatus is presented for measuring jitter tolerance in a device under test. A device under test is established to operate at a specific frequency. A bit pattern is generated from a bit pattern generator. The bit pattern generated by the bit pattern generator is produced at a frequency that is a multiple of the frequency that the device under test is operating under. Bits are systematically changed in the bit pattern and then errors are measured in the device under test. As a result, the jitter tolerance of the device under test is measured.

Abstract: A method and apparatus is presented for measuring jitter tolerance in a device under test. A device under test is established to operate at a specific frequency. A bit pattern is generated from a bit pattern generator. The bit pattern generated by the bit pattern generator is produced at a frequency that is a multiple of the frequency that the device under test is operating under. Bits are systematically changed in the bit pattern and then errors are measured in the device under test. As a results the jitter tolerance of the device under test is measured.

Abstract: A method and apparatus is presented for measuring jitter tolerance in a device under test. A device under test is established to operate at a specific frequency. A bit pattern is generated from a bit pattern generator. The bit pattern generated by the bit pattern generator is produced at a frequency that is a multiple of the frequency that the device under test is operating under. Bits are systematically changed in the bit pattern and then errors are measured in the device under test. As a result, the jitter tolerance of the device under test is measured.